The invention pertains to systems and methods for calculating the amount of fluid transferred over one or more time intervals. More particularly, the invention pertains to such systems which make calculations based on predetermined flow rates.
Various types of pump control or fluid transfer control systems are known. Pumping is often initiated in response to rising fluid levels and ceases when the respective fluid level has been restored to an expected nominal value.
There are circumstances where it is desirable to be able to determine the amount of fluid that has been transferred. Alternately, there are circumstances where it is desirable to be able to establish a program for cycling one or more pumps on and off and also for keeping running totals of quantities of fluid which have been transferred or pumped.
There is a continuing need to be able to implement the above identified functions in a cost effective way in smaller systems. It would be desirable to simply and inexpensively be able to keep track of quantities of transferred fluid.
A flow meter in accordance with the present invention provides a measure of quantity of flow transferred during one or more time intervals by one or more pumps. One or more of flow rate parameters is manually entered into the system. Entry can be by keypad or by any other convenient user manipulatable interface. Flow rate can be entered for example in gallons per minute, liters per second, and so on.
A real time clock is provided to keep track of elapsed time which is indicative of time when the fluid in question is being transferred. Where the flow meter is used with an external pump control system, a start command is received from the external system. This command causes the real time clock to begin to measure the pumping time interval, for example by accumulating pulses in a buffer. When the pump motor is shut off and the start command has returned to a non-pumping state, the count in the buffer is indicative of the time interval during which the fluid was being transferred
The time interval can be multiplied by the previously entered and stored flow rate parameter to establish the quantity of fluid which has been transferred during the measured time interval. The units of volume or quantity of fluid which has been transferred can be displayed on a local display for the user.
The amount of fluid which has been transferred or pumped in addition to being displayed can be stored in internal non-volatile memory for future use. As the pump continues to cycle and the start command initiates additional counting intervals in the flow meter, the various quantities of fluid associated with each of the pumping cycles can be accumulated in non-volatile memory. Each of the quantities of fluid during the respective pumping cycles can be displayed. The total amount of fluid pumped since the last system re-set can also be displayed.
In one embodiment, a user can enter a control program establishing time on/time off intervals for a plurality of pumps such as in an irrigation system or in a residential watering system. A processor in the system can execute the program and, based on an entered flow rate parameter, can accumulate in memory quantities of fluid pumped during each pumping cycle by each of the motors. Thus, the proprietor of a residence, commercial establishment or farm, for example, can easily control the on/off sequencing of a plurality of pumps during a time interval, for example, 24 hours. In addition, a running, accurate total of fluid that has been pumped can be maintained and can be used in establishing expected charges for the fluid.
The present flow meter can be used in a stand-alone mode for the purpose of calculating short term or long term quantities of transferred fluid in a system. In this mode, the user would initially program the system with flow rate data based upon either empirical or measured data. The system, in response to a start command or other signal could keep track and store the time durations during which the pump or pumps is or are active. The quantity of fluid pumped during each interval can be stored in system memory. The quantities pumped during each cycle can be viewed along with total quantities of pumped fluid.
In yet another aspect, the flow meter could function as a user programmable pump-timer/controller. In this embodiment, the user can program the meter with pump on/off interval information on a daily, weekly, or monthly basis. The meter can in turn activate the pump or pumps for the programmed time intervals at the programmed times.
In yet another embodiment, the meter can be programmed to perform auxiliary control functions. For example, during a chlorine dosing process, chlorine is added to a septic mixture to maintain specific bacterial concentrations. The amount of chlorine added is a function of the volume of septic material which has been pumped or transferred during a respective time interval.
Based on pre-established quantities of fluid or pump running time intervals or other predetermined intervals, chlorine or other processing chemicals or materials can be added to the transferred fluid. In this regard, a user can select one member of a plurality of dosing processes. Processes can include adding quantities of a chemical, such as chlorine, to a septic mix after some predetermined quantity, such as 40 gallons, of mix have been transferred. Alternately, a quantity of chemical or other material can be added after a predetermined interval of pump run time, such as for example 3 hours, 4 hours, or 72 hours.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.